When Roger Frick restored the Branch Mint Porter I Believe that the original lettering was done in Gold Leaf.
That being said the 10th edition of Porters catalog gives the following
Code word
TAMIZO... Extra hansome finish and painting,gold lettering.
TAMPON...Very plain finish, durable, but without ornament
From the 13 edition (reprinted by the NMRA)
ROJIZO...Boiler lagged with asbestos cement and cased with planished iron
ROKADS...Boiler lagged with wood over asbestos sheet and cased with sheet steel painted.
ROKABE... Boiled casing withn securing bands of same erial as casing.
ROLHAO... Boiler casing with brass securing bands.
I guess you took your choice and paid your money.
Dave g